Bearing assembly with spacer for locating a seal sleeve

ABSTRACT

A bearing assembly for supporting a shaft comprising a support cartridge, a seal and a spacer is provided. The seal may be a multi-component seal including an outer ring and an inner sleeve, which rotates with the shaft. The seal&#39;s outer ring may have a first inwardly projecting annular lip, a second inwardly projecting annular lip and an annular groove defined between the first lip and the second lip. The seal&#39;s inner sleeve may have a peripheral flange retained in the outer ring&#39;s annular groove. The spacer is adapted to axially locate the inner sleeve&#39;s flange. Particularly, the spacer is configured for locating the inner sleeve&#39;s flange in the groove of the outer ring so that the flange does not contact either the first lip or the second lip during operation. The spacer may axially locate the inner sleeve such that the inner sleeve&#39;s collar contacts an inwardly-extending sealing ring.

CROSS-REFERENCE TO RELATED APPLICATIONS

None.

BACKGROUND OF THE INVENTION

Bearing assemblies are well known and are commonly used to supportshafts, axles and other rotating components that may be present invarious types of industrial equipment, vehicles and other machinery.Such bearing assemblies often include seals to form barriers in order topreclude the entry of external contaminants into the bearings and alsoto preclude lubricants from escaping from within the bearings. Theseseals each typically include a flexible seal portion. In some cases, theseals include multiple components, wherein one or more of the componentsrotate with the shaft and other components remain static.

There are certain difficulties that must be addressed with seals thatinclude both rotating and non-rotating components, as metal-on-metalcontact between the components can lead to friction and wear. When thisoccurs, the seal may become damaged or destroyed resulting in a bearingfailure. Unfortunately, the replacement of a damaged seal and/or bearingcan be difficult, time-consuming and usually results in an extendedperiod of down time during which the machinery is out of service.

Thus, a need exists for a bearing assembly in which rotating metalliccomponents are not in contact with non-rotating metallic components ofthe assembly. A further need exists for a means for axially locating andretaining one or more of the components of a multi-component seal oncethe seal has been installed into the bearing assembly.

SUMMARY OF THE INVENTION

One embodiment of the present invention involves the provision of abearing assembly for supporting a rotating shaft. The bearing assemblycomprises a support cartridge, a multi-component seal and a spacer. Thesupport cartridge has an axial bore defined therethrough formed by aninner wall. The support cartridge's inner wall can include one or moreshoulders defined therein for locating one or more of the bearing, sealand spacer. The multi-component seal can include an outer ring, an innersleeve and a sealing ring. The outer ring, which remains static when theshaft rotates, may comprise a first inwardly projecting annular lip, asecond inwardly projecting annular lip and an annular groove definedbetween the first lip and the second lip. The inner sleeve, whichrotates with the shaft, may include a peripheral flange that is retainedin the outer ring's annular groove. The outer ring and inner sleeve maybe constructed of stainless steel or other suited metallic materials.The sealing ring, which may be constructed of a flexible material suchas an elastomer, extends radially inwardly from the outer ring and is insealing contact with a collar portion of the inner sleeve. The sealingring remains static when the shaft rotates.

The spacer is adapted to axially locate the inner sleeve's flange suchthat it is not in contact with any metallic element of the assemblyconfigured to be static when the shaft is rotating. Particularly, thespacer is configured for locating the inner sleeve's flange in thegroove of the outer ring so that the flange does not contact either thefirst lip or the second lip. The spacer can also serve to locate theinner sleeve to ensure that the sealing ring contacts the outer diameterof inner sleeve collar and not the shaft. The inner sleeve collar canhave hardness and surface finish specifications, as defined by therequirements of the sealing ring, that the shaft may not possess.

A method for manufacturing and assembling the bearing assembly is alsoprovided. In the method, the multi-component seal is slid onto the shaftor placed into the bore of the support cartridge. The spacer is thenslid onto the shaft or placed into the bore of the support cartridge.The spacer may be engaged by the inner race of the bearing when thebearing is installed. The spacer in turn engages and locates the innersleeve of the multi-component seal such that its flange is not incontact with any metallic element configured to be static when saidshaft is rotating, including the outer ring's first and second lips. Thespacer can also locate the inner sleeve to ensure that the sealing ringcontacts the outer diameter of inner sleeve collar and not the shaft.

Other and further objects of the invention, together with the featuresof novelty appurtenant thereto, will appear in the course of thefollowing description.

DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

In the accompanying drawing, which forms a part of the specification andis to be read in conjunction therewith in which like reference numeralsare used to indicate like or similar parts in the various views:

FIG. 1 is an exploded perspective view of a bearing cartridge assemblyin accordance with a first embodiment of the present invention;

FIG. 2 is a sectional perspective view of the bearing cartridge assemblyof FIG. 1;

FIG. 3 a is a partial sectional side view of the bearing cartridgeassembly of FIG. 1;

FIG. 3 b is an enlarged partial sectional side view of the bearingcartridge assembly of FIG. 1 corresponding to the portion 3 b of FIG. 3a;

FIG. 4 is an exploded perspective view of a bearing cartridge assemblyin accordance with a second embodiment of the present invention;

FIG. 5 is an sectional perspective view of the bearing cartridgeassembly of FIG. 4;

FIG. 6 is a partial sectional side view of the bearing cartridgeassembly of FIG. 4;

FIG. 7 is an exploded perspective view of a bearing cartridge assemblyin accordance with a third embodiment of the present invention;

FIG. 8 is a sectional side view of the bearing cartridge assembly ofFIG. 7;

FIG. 9 is an exploded perspective view of a bearing cartridge assemblyin accordance with a fourth embodiment of the present invention;

FIG. 10 is a sectional side view of the bearing cartridge assembly ofFIG. 9;

FIG. 11 is an exploded perspective view of a bearing cartridge assemblyin accordance with a fifth embodiment of the present invention; and

FIG. 12 is a sectional side view of the bearing cartridge assembly ofFIG. 11.

DETAILED DESCRIPTION OF THE INVENTION

The invention will now be described with reference to the drawingfigures, in which like reference numerals refer to like partsthroughout. For purposes of clarity in illustrating the characteristicsof the present invention, proportional relationships of the elementshave not necessarily been maintained in the drawing figures.

The following detailed description of the invention references specificembodiments in which the invention can be practiced. The embodiments areintended to describe aspects of the invention in sufficient detail toenable those skilled in the art to practice the invention. Otherembodiments can be utilized and changes can be made without departingfrom the scope of the present invention. The present invention isdefined by the appended claims and the description is, therefore, not tobe taken in a limiting sense and shall not limit the scope ofequivalents to which such claims are entitled.

The present invention is directed generally to a bearing cartridgeassembly 10 for supporting an axle or shaft 12. FIGS. 1-3 b illustrate afirst embodiment of the assembly 10 comprising a support cartridge 14, abearing 16, a spacer 18 and a multi-component seal 20. Additionally,FIGS. 4-6 illustrate a second embodiment of the assembly 10, FIGS. 7-8illustrate a third embodiment of the assembly 10, FIGS. 9-10 illustratea fourth embodiment of the assembly 10 and FIGS. 11-12 illustrate afifth embodiment of the assembly 10. It will be appreciated that otherembodiments, not explicitly shown in the figures, are also within thescope of the present invention.

The assembly 10 of the present invention is suitable for operation in avariety of applications and environments. In one embodiment, theassembly 10 is designed for use with a rotary airlock, such as onesuitable for the pneumatic conveying of particulate materials, as wellas diverter valves, splitter valves and bucket valves on materialhandling equipment. Additionally, it will be understood that theassembly 10 may be used in connection with other equipment, such asautomobiles, industrial equipment, construction equipment, agriculturalequipment and other machinery. In one embodiment, the assembly 10 isdesigned for use in a wheel bearing assembly.

The support cartridge 14 may include a hub or collar 22, an annularmounting flange 24 and an axial bore 26 extending through the collar 22and flange 24. The axial bore 26 is defined by an inner wall 28 of thesupport cartridge 14. The inner wall 28 of the support cartridge 14 caninclude one or more stops against which a bearing 16, spacer 18 ormulti-component seal 20 may be seated. In one embodiment, the stops arein the form of shoulders 30, 32 and 34 defined in the wall 28 that formsthe bore 26. In another embodiment, the stops may be created by snaprings that are received in annular grooves defined in the wall 28.

The mounting flange 24 of the support cartridge 14 can include amounting face 36 adapted for mating with, for example, the exteriorsurface 38 of an end plate 40 of a rotary airlock or other suitablepiece of equipment. In order to seal the mounting flange 24 to the endplate 40, the mounting face 36 may have a groove 42 defined thereinsuitable for receiving an O-ring 44. The mounting flange 24 can alsoinclude a plurality of apertures 46 defined therethrough designed forreceiving a fastener, such as a bolt (not shown), for securing thesupport cartridge 14 to the end plate 40. These apertures 46 may beunthreaded or threaded. The mounting flange 24 may also have one or morethreaded apertures 48. During the process of removing the assembly 10from the end plate 40, a bolt (not shown) can be screwed into thesethreaded apertures 48, and against the end plate 40, in order to aid inbreaking away a support cartridge 14 that is seized to the end plate 40.When the bolts contact the end plate 40, they push the support cartridge14 away from the end plate 40. As shown, the apertures 46 and threadedapertures 48 may be arranged in an alternating pattern.

The bearing 16 may be of any suitable type including, for example, aball bearing, roller bearing, tapered roller bearing, needle bearing orthe like. As is well known, the bearing 16 can include an inner race 50,having first and second opposing surfaces 52 and 54, and an outer race56, having first and second opposing surfaces 58 and 60. The innerdiameter of the bearing's inner race 50 is sized such that the bearing16 fits around a portion 62 of the shaft 12. As shown, when assembled,the second surface 60 of the bearing's outer race 56 may be seatedagainst a shoulder 32 defined in the wall 28. In operation, thebearing's outer race 56 is static and the bearing's inner race 50rotates with the shaft 12.

The multi-component seal 20 may be any suitable seal now known orhereafter developed. In one embodiment, the multi-component seal 20comprises an outer ring 68, an inner sleeve 70 and a sealing ring 66.The outer ring 68 may be formed of a plurality of individual components.As illustrated, the outer ring 68 includes a first inwardly projectingannular lip 72, a second inwardly projecting annular lip 74 and anannular groove 76 defined between the first lip 72 and second lip 74.The outer ring's first and second lips 72 and 74 may be constructed of ametallic material, such as stainless steel. The first inwardlyprojecting annular lip 72 may be in the form of a removable snap ring.The inner sleeve 70, which may also be constructed of a metallicmaterial, includes a peripheral flange 78 having a first surface 80 anda second surface 82. As depicted in FIG. 3 b, the thickness T_(f) of theflange 78 is less than the thickness T_(g) of the groove 76 such thatthe flange 78 may be received in the groove 76. As will be discussed ingreater detail below, the flange 78 can be located in the groove 76 sothat a first space S₁ is formed between the flange's first surface 80and the outer ring's first lip 72 and a second space S₂ is formedbetween the flange's second surface 82 and the outer ring's second lip74. This prevents the metallic flange 78, which rotates with the shaft12, from contacting the metallic lips 72 and 74 of the outer ring 68,which is static. Additionally, the outer diameter of the flange 78 isless than the inner diameter of the groove 76 thereby resulting in aradial space S₃ therebetween. As shown, the inner sleeve 70 furtherincludes a collar portion 84 having an outer surface that is engaged bythe sealing ring 66 which extends radially inwardly from the outer ring68. The sealing ring 66 may be constructed of a flexible material, suchas an elastomer like polytetrafluoroethylene (PTFE) or any othermaterial suitable for creating a seal. As demonstrated, the sealing ring66 is in sealing contact with an outer surface of the sleeve's collarportion 84.

As illustrated, the first portion 62 of the shaft 12 has a diameter thatis less than the diameter of the second portion 64. While the shaft 12is depicted as having a stepped profile with two different diameters, itwill be understood that the shaft 12 need not be stepped and may be of asingle, uniform diameter.

As mentioned above, when assembled, the flange 78 of the inner sleeve 70is not in contact with the outer ring 68. This is achieved through theuse of a spacer 18. The inner diameter of the inner sleeve 70 may beapproximately equal to the diameter of the second portion 64 of theshaft 12 such that inner sleeve 70 must be pressed onto the shaft 12. Assuch, when the multi-component seal 20 is slid or pressed onto the shaft12, the inner sleeve 70 drags along the outer surface of the shaft 12.Because the inner sleeve 70 drags along the outer surface of the shaft12, the inner sleeve's flange 78 may become pressed against the outerring's first lip 72. The spacer 18 is provided to axially locate theinner sleeve 70, and particularly the flange 78 of the inner sleeve 70.After the multi-component seal 20 is slid onto the shaft 12, the spacer18 may be slid onto the shaft 12 to axially locate the flange 78 of theinner sleeve 70.

In the embodiment illustrated in FIGS. 1-3 b, the support cartridge 14has shoulders 30 and 32 defined therein. The multi-component seal 20 isseated against shoulder 30 and the bearing's outer race 56 is seatedagainst shoulder 32. The shoulders 30 and 32 are spaced a distance fromone another such that when the bearing's outer race 56 becomes seatedagainst shoulder 32, the spacer 18 has pushed the flange 78 of the innersleeve 70 so that it is located between, and not in contact with, thefirst and second lips 72 and 74 of the outer ring 68 of themulti-component seal 20. Put differently, the spacer 18 is of athickness T_(s) such that when it is contacted by the bearing's innerrace 50, the spacer 18 pushes the flange 78 of the inner sleeve 70 sothat it is located between, and not in contact with, the first andsecond lips 72 and 74 of the outer ring 68 of the multi-component seal20. As such, once assembled, the flange 78 of the inner sleeve 70 (whichrotates with the shaft) is not in contact with the outer ring 68 (whichremains static when the shaft turns). This lack of metal-on-metalcontact prevents friction and wear thereby increasing the lifespan ofthe multi-component seal 20. It will also be understood that the spacer18 may locate the inner sleeve 70 so that the sealing ring 66 is incontact with the outer surface of the inner sleeve's collar 84.

The spacer 18 has first and second opposing surfaces 86 and 88. In theembodiment illustrated in FIGS. 1-3 b, the second surface 54 ofbearing's inner race 50 engages the first surface 86 of the spacer 18.The second surface 88 of the spacer 18 in turn engages the first surface80 of the inner sleeve's flange 78 in order to position the flange 78within the groove 76.

It will be understood that the following components are static when theshaft 12 is rotating: the support cartridge 14, the bearing's outer race56 and the outer ring 68 of the multi-component seal 20, including thesealing ring 66. Likewise, it will be understood that the followingcomponents rotate with the shaft 12 when the shaft 12 is rotating: thebearing's inner race 50, the spacer 18 and the inner sleeve 70 of themulti-component seal 20. In another embodiment, spacers may be providedon either or both sides of the inner sleeve 70 in order to position theflange 78 between the outer ring's first and second lips 72 and 74.

In another embodiment, for example an embodiment designed for use with awheel hub and bearing assembly, the shaft 12 (which may be an axleshaft) remains static. In this embodiment, it will be understood thatthe following components may always remain static with the shaft 12: thebearing's inner race 50, the spacer 18 and the inner sleeve 70 of themulti-component seal 20. Likewise, it will be understood that thefollowing components may rotate when the support cartridge 14 (which maybe a wheel hub) is rotating: the bearing's outer race 56 and the outerring 68 of the multi-component seal 20, including the sealing ring 66.

It will be appreciated by one skilled in the art that the seal 20 neednot be a multi-component seal. Instead, the seal 20 may be comprised ofan unconstrained sleeve that is not restrained by an outer ring, as isthe case with a multi-component seal. The spacer 18 may be adapted forengaging the unconstrained sleeve of seal 20 in order to locate theunconstrained sleeve to ensure that the sealing ring 66 contacts theouter surface of the unconstrained sleeve and not the shaft 12.

Turning now to the embodiment of the assembly 10 depicted in FIGS. 4-6,it will be appreciated that this embodiment may be particularly wellsuited for use in a wheel bearing application. This embodiment includesa support cartridge 14, a bearing 16, a spacer 18 and a multi-componentseal 20, as well as a spacing insert 94, a lock nut 96, a lock washer 98and shaft seals 100 and 102. As shown, the bearing 16 is a taperedroller bearing. As further illustrated, the spacer 18 may comprise aperipheral flange portion 90 and a collar portion 92. Additionally, thespacer 18 may be pushed into place by a seal 102, as opposed to thebearing 16. The seal 102 may be seated against shoulder 34 and remainsstatic. Therefore, the dynamic spacer 18, which may contact the staticseal 102, may be constructed of a polymer material, such as PTFE, toprevent metal on metal friction and wear.

In the embodiment shown in FIGS. 7-8, the spacer 18, which can beconstructed of a polymer material to prevent metal on metal contact, maybe retained in place by an annular protrusion 108 extending inwardlyfrom the inner wall 28 of the support cartridge 14. In the embodimentdepicted in FIG. 9-10, the spacer 18 may be comprised of a plurality ofshim or washer members 110, which may have a combined thickness selectedto correspond to the dimensions of a particular support cartridge 14 andmulti-component seal 20. Additionally, in the embodiment shown in FIGS.11-12, the spacer 18, which can be constructed of a polymer material toprevent metal on metal contact, may be retained in place by a snap ring112 that is received in an annular groove 114 defined in the inner wall28 of the support cartridge 14.

A method for manufacturing and assembling a bearing cartridge assembly10 is also provided. In the method, the multi-component seal 20, such asa multi-component seal having an outer ring 68 and an inner sleeve 70,is slid onto the shaft 12 or placed into the bore 26 of the supportcartridge 14. A spacer 18 is then slid onto the shaft 12 or placed intothe bore 26 of the support cartridge 14. The spacer 18 may be engaged bythe inner race 50 of the bearing 16 when the bearing 16 is installed.The spacer 18 engages and locates the inner sleeve 70 such that itsflange 78 is not in contact with any element configured to be staticwhen said shaft 12 is rotating. Specifically, the spacer 18 may locatethe flange 78 in between the first and second inwardly projectingannular lips 72 and 74 of the outer ring 68 so that the flange 78 is notin contact with either lip 72 and 74.

From the foregoing, it will be seen that this invention is one welladapted to attain all the ends and objects hereinabove set forthtogether with other advantages which are obvious and which are inherentto the structure. It will be understood that certain features and subcombinations in addition to those shown and discussed herein arepossible. This is contemplated by and is within the scope of the claims.Since many possible embodiments of the invention may be made withoutdeparting from the scope thereof, it is also to be understood that allmatters herein set forth or shown in the accompanying drawings are to beinterpreted as illustrative and not limiting.

The constructions and methods described above and illustrated in thedrawings are presented by way of example only and are not intended tolimit the concepts and principles of the present invention. Thus, therehas been shown and described several embodiments of a novel invention.As is evident from the foregoing description, certain aspects of thepresent invention are not limited by the particular details of theexamples illustrated herein, and it is therefore contemplated that othermodifications and applications, or equivalents thereof, will occur tothose skilled in the art. The terms “having” and “including” and similarterms as used in the foregoing specification are used in the sense of“optional” or “may include” and not as “required”. Many changes,modifications, variations and other uses and applications of the presentconstruction will, however, become apparent to those skilled in the artafter considering the specification and the accompanying drawings. Allsuch changes, modifications, variations and other uses and applicationswhich do not depart from the spirit and scope of the invention aredeemed to be covered by the invention which is limited only by theclaims which follow.

What is claimed is:
 1. A bearing cartridge assembly comprising: asupport cartridge having an axial bore defined therethrough; amulti-component seal including an outer ring and an inner sleeve,wherein said outer ring has a first inwardly projecting annular lip, asecond inwardly projecting annular lip and an annular groove definedbetween said first lip and said second lip, and wherein said innersleeve has a peripheral flange retained in said outer ring annulargroove; and a spacer for axially locating said inner sleeve flange. 2.The bearing cartridge assembly of claim 1, wherein said spacer axiallylocates said inner sleeve flange in said groove such that said innersleeve flange does not contact either of said first lip and said secondlip.
 3. The bearing cartridge assembly of claim 1, wherein said innersleeve includes a collar portion and wherein outer ring includes asealing ring extending radially inwardly therefrom and in contact withan outer surface of said collar portion.
 4. The bearing cartridgeassembly of claim 3, wherein said spacer axially locates said innersleeve such that said collar of said inner sleeve contacts said sealingring.
 5. The bearing cartridge assembly of claim 3, wherein said outerring is configured to be static and wherein said inner sleeve isconfigured to rotate with said rotating shaft.
 6. The bearing cartridgeassembly of claim 3 further comprising a bearing having an inner raceand an outer race, and wherein said bearing inner race, said spacer andsaid inner sleeve rotate with said rotating shaft.
 7. The bearingcartridge assembly of claim 1, wherein said spacer includes first andsecond opposing surfaces and said inner sleeve flange includes first andsecond opposing surfaces, and wherein said spacer second surface engagessaid inner sleeve flange first surface in order to axially locate saidinner sleeve flange between said first lip and said second lip.
 8. Thebearing cartridge assembly of claim 1, wherein said spacer is comprisedof a plurality of shims.
 9. The bearing cartridge assembly of claim 1,wherein said support cartridge includes a stop against which said outerring of said multi-component seal is seated.
 10. The bearing cartridgeassembly of claim 9, wherein said stop is a shoulder defined in a wallthat forms said bore.
 11. The bearing cartridge assembly of claim 9,wherein said stop is a snap ring received in an annular groove definedin a wall that forms said bore.
 12. The bearing cartridge assembly ofclaim 1, wherein said support cartridge includes an annular mountingflange having a plurality of threaded apertures defined therethrough andadapted for receiving bolts for pushing said support cartridge away froma structure to which it is mounted.
 13. A bearing cartridge assemblycomprising: a support cartridge having an axial bore definedtherethrough; a sleeve configured for creating a seal against a rotatingshaft; and a spacer for axially locating said sleeve relative to saidshaft.
 14. The bearing cartridge assembly of claim 13, furthercomprising a multi-component seal including an outer ring having a firstinwardly projecting annular lip, a second inwardly projecting annularlip and an annular groove defined between said first lip and said secondlip.
 15. The bearing cartridge assembly of claim 14, wherein said sleeveincludes a peripheral flange that is retained in said annular groove ofsaid outer ring.
 16. The bearing cartridge assembly of claim 15, whereinsaid spacer axially locates said sleeve flange in said groove such thatsaid sleeve flange does not contact either of said first lip and saidsecond lip.
 17. A method for manufacturing a bearing cartridge assembly,said method comprising the steps of: providing a support cartridgehaving an axial bore defined therethrough; providing a sleeve having aperipheral flange, said sleeve being configured for creating a sealagainst a rotating shaft; and providing a spacer for axially locatingsaid sleeve flange; placing said sleeve onto said shaft or into saidbore; and placing said spacer onto said shaft or into said bore tolocate said sleeve flange such that said flange is not in contact withany metallic element configured to be static when said shaft isrotating.
 18. The method of claim 17, further comprising amulti-component seal including an outer ring having a first inwardlyprojecting annular lip, a second inwardly projecting annular lip and anannular groove defined between said first lip and said second lip. 19.The method of claim 18, wherein said peripheral flange of said sleeve isretained in said annular groove of said outer ring.
 20. The method ofclaim 19, wherein said spacer axially locates said sleeve flange in saidgroove such that said sleeve flange does not contact either of saidfirst lip and said second lip.